The present invention comprises a new and distinct cultivar of plum hybrid Prunus besseyi×P. cerasifera used as a rootstock known by the varietal name ‘Densipac’. The new variety was discovered in Barcelona, Spain in 1998 as a result of a planned breeding program. The new variety is the result of a cross between an unnamed clone of P. besseyi (female parent, unpatented) and an unnamed clone of P. cerasifera (male parent, unpatented). The purpose of the breeding program was to develop a low vigor rootstock with good capacity to control vigor, adapted to Mediterranean conditions, compatible with peach and nectarine varieties, with a high tolerance to poorly drained clayish soils that suffer from water-logging conditions. The new variety exhibits similar good tolerance to calcareous soils, moderate root-knot nematode resistance, and resistance to several soil-borne fungi, especially Rosellinia necatrix. The genotype has medium chilling requirements and good productivity. It differs from both parents in its leaf shape, vigor, and the fact that it better tolerates water logging conditions. Further, the new variety has similar vigor, tolerance to iron chlorosis, and root-knot nematode resistance to plum hybrid ‘Saint Julien 655-2’ (unpatented), but differs from ‘Saint Julien 655-2’ in its improved compatibility with peach, nectarine, and some almond varieties, no root suckering, lesion nematode resistance, resistance to Rosellinia necatrix (soil-borne fungus), leaf morphology, and lower chill requirements. The new variety has been trial and field tested and has been found to retain its distinctive characteristics and remain true to type through successive propagations. The following characteristics distinguish ‘Densipac’ from other varieties known to the breeder:                1. Low vigor with a small trunk cross-section area;        2. High capacity to control tree vigor when grafted with peach and nectarine varieties (recommended use);        3. High tolerance to root asphyxia;        4. Better tolerance to alkaline soils than most peach rootstocks;        5. Moderate resistance to root-knot nematodes (Meloidogyne spp.);        6. Resistance to the lesion nematode Pratylenchus vulnus;         7. Induces early fruit maturation in peach varieties;        8. Induces larger sized fruit in peach and nectarine varieties;        9. Medium chilling requirements within the range of 600 to 800 cu.; and        10. Resistance to the white root rot fungus Rossellia necatrix.         